Optical data storage media are often utilized to store data such as music, computer programs, movies, audio books, and the like. While it is generally desirable for data storage media to have long service lifetimes, it is sometimes desirable, in certain applications, to limit the life of the storage media. For example, sample computer programs are often provided to potential customers in order to entice them to purchase the software. These programs are intended to be used only for a limited period of time in order to protect the intellectual property rights of the owner(s). In addition, music and movies are currently rented to customers for a limited time period after which they need to be returned. There is also a desire on the part of movie studios as well as the music industry to minimize the piracy of movies and music respectively. In each of the aforementioned applications, it would be desirable to minimize the time-period for which the data storage media can be actively utilized, following which the media becomes unusable.
In order for the limited play media to be a viable product, it must have sufficient quality when it is first used. The quality should then degrade to unusable in a predetermined period of time. Finally, once unusable, the limited play functionality should not be reversible. If the method for providing limited play to data storage media can be easily defeated by a customer or a cottage industry, the data storage media would no longer be “limited-play”. In the case of a coating or material rendering an optical disk unplayable, for example, facile removal or modification of that coating and/or material could provide a disk with unlimited playability. Therefore the attainment of limited play features in optical data storage media without being easily defeatable is a feature that is widely sought after.